Drying machine



March 31, 1925- "1,532,097 T. ALLSOP ET AL DRYING MACHINE Filed Aug. 11, 1920 2 Sheets-Sheet 1 V m I I y N l g N w FIG:

- Fla; 1.

I INVENTORS: v /msssfiafifi v Thomas flllsopgf mlieflk'siasoig ATTORNEYS.

-March 31, 1925- v T. ALLSOP ET AL DRYING MACHINE 2 Sheets-Sheet 2 A TTORNEYS v INVENTORS: Thomas fllls'qvgf Walter WSifi Filed Aug. 11, 1920 Patented Mar. 31 l925.

omrro 1,532,0i-EZ- PATENT OFFICE.

THOMAS ALLSOP A-ND wen'rnnw. .srsson, on PHILADELPHIA, PENNSYLVANIA, AS- SIGNOBS re mun PHILADELPHIA DRYING arAoHINnnY COMPANY, or PHILA- D LPHIA, BENNSYLVANIA, A CORPORATION or PENNSYLVANIA.

DRYING MACHINE.

applic ti 1 5 Ass s .21. s al :NO- 4 .2. .4:-

T al h m i may-new r "Be l l Al l 'Wl% Tw ne siIS an Wor ies, steamer he U ited States, residing" "glihiladelphia, in" the county 2 Ph lade p i an i aro P n SyM iaihaW i ent cert i ne -en i ful Improyements ,in Drying lllachines, whereof the following is a specification, reference;heing hadeto the accompanying draw wa 1 The invention inlates to machines useful in d yinema e ziels ara le of being e ported on trays, such for example as chemical product regetables, frui em, a d more particularly to the type in which the direction v o'fl'fiow of stheciiying medium is reversed .at intervals so that the same may be caused to impinge from ,opposite sides .upo n gthe materials under treatment in-order to secure ,uniiormity in drying.

' The object of our invention .is to insure that the temperature of the drying medium impinging upon thGgfiltiClGS is thesame re gardlessof the direction of approach. This we accomplish by disposing the materials to h l i -Qd n :the spaces between a number of heating coil banks located at intervals withina ryi g' c amber, a'sui abl bypa eing providedfby [way o flwhieh the drying medium ,may enter the drying chamber al- .tern ely immflepnos e e d un e t ceon efi nr epr e .n pe l n in an T h ad antage 'o ou n e tion w l h c e appare i em he d a led deSQ iPtiOn which follows. i

lath dr i s llsi a t ens dine sectional view through a drying ,machine .conren entlyembod n o r twe t es Fig &1 i a r s ectienal r ewse th same along ,the plane of the arrows AIL-r111 Fig. I.

' rFigs. I11 and TV ,are illustrations similar -,to Figs I and II show.ing a slightly modified embodiment of our invention.

ZRefenring first to the structure illustrated in figs. 1 and II, it will he observedth-at -the same is in the form of an enclosure .1 having the cross sectional configuration clearly shown in the former. of said fig ures. Theenclosureis subdivided by a horizontal diaphragm 2 into a drying chamber '3 and a coextensive auxiliary passage A. Therdiaphragm 2 terminates short of :the end walls and 6 of the enclosure 1 time by aifordjng communication openings 7 and 8 hetween the drying chamber 3 and: the a ug l ary ipassage l, .so that the latter ma be utilized as a return duct for an airfcirculatory course .within' the enclosure. A

vertical bank of heating coils 10 is located p,osed -relation-and are at the same time suit ablyspaced apart topermit free flow. of

,the drying medium between them. It is to noted ,that the ntervals betwee11 tl1e trays 13 of the several columns of the rack structure are 'in alignment, thus establishing a Series ,ofconti-nuous, horizontal channels between which the flow of thedrying medium divides evenly when circulated, as suggested by the arrows in Fig. I. This circulat ion is maintained through the instrumentalityof a rotary fan 15 mounted in a .CilTQllhlYopening 1 6 of a vertical longitudinal partition 17 which spans the auxiliary passage 51-. The fan 15 is secured upona shaftlfi which extends to the exterior, and is journalled in bearings 19 and 20. To one end of the shaft is attached an actuating pulley 21 shown as being belted to a coordinative pulley 22 on an overhead power By following the course suggested by the arrows an Fig. I, it will be apparent that the air traversing the drying chamber 3 is obliged, .by reason of the arrangement of the trays 13, to subdivide evenly through the interveniiig horizontal channels, and, as a consequence, :to impinge uniformly upon the materials supported by said trays. The same reasoning will obviously hold for circulation in the opposite direction. In either case, the distribution of the heating coil banks 10, 10 at different points in the course will be conducive toward maintaingillg the temperature in all portions of the ment.

to the proper temperature before entering the flow channels intermediate the supporting trays l3, l3 regardless of the direction of circulation. This feature is highly important when the character of the materials is such as to require occasional change in the direction of flow of the drying medium to obtain satisfactory results. For example in the case of the treatment of materials having a tendency to warp or each, it is essential that the direction of flow be periodically reversed, whereby the drying medium may be caused-to impinge upon them alternately from opposite sides so that uniform drying may be accomplished without danger of warping of the materials.

Thus it will be seen that it is extremely important that the temperature undr the aforesaid conditions be absolutely uniform.

The modified form of our invention shown in Figs. III and IV differs only slightly from the embodiment first described, and corresponding parts have therefore been identified with the same reference characters. Subdivision of the enclosure 1 and the general interior arrangement are the same as before, but, in this instance, the supporting trays 30, instead of being mounted in fixed racks are carried by trucks 31, 31, the trays being, however, placed in superposed relation and spaced apart so as to afford the aligned horizontal flow channels corresponding to those previously described in connection with. the first embodi- The modified structure differs still in one other particular in that an additional bank of heating coils 32 is interposed between the trucks 31, 31. If the capacity of the drier be such as to accommodatemore than two trucks 31, additional coils would be interposed between each adjacent pair of trucks of the series. By such allocation of the heating coils at intervals within the drying chamber, the temperature in all parts of the same may be obviously maintained practically constant so that the materials under treatment in the intervals between the coil banks are, as a result, uniformly dried under the movement of the air within the structure.

Having thus described our invention, we claim:

1. A drying machine comprising a casing including-a drying chamber and a communicating channel for the continuous circulation of air from the channel through the drying chamber and back, and air propelling means located in the channel exteriorly of the heating chamber, means within the heating chamber for supporting the materials to be dried, and heat radiating elements located at each side of the material supporting means and disposed within the path of air circulation.

2. A drying machine comprising a casing including a drying chamber, and a communicating channel for the continuous circulation of air from the channel through the drying chamber and back, an air propelling means located in the channel, means within. the drying chamber for supporting materials to be dried, and banks of heat radiating elements located at either side of the material supporting means and of substantially equal radiating capacity, the air propelling means being alternately actuable to force air through the drying chamber In one direction or the other, whereby to effect uniform drying of materials during the flow of air in either direction.

3. A drying machine comprising a casing including a drying chamber and a communicating passage for the continuous circulation of air from the passage through the drying chamber and back, an air propolling means located in the passage, a pair of end heat radiating elements of substantially equal radiating capacity located in the drying chamber, an intermediate heat ing element. and means located in the spaces between said elements for supporting the materials to be dried, the air propelling means being actuable to cause flow of the air through the drying chamber alternately in opposite directions, whereby the materials are subjected to cause uniform dehydration in either direction of flow.

i. A drying machine comprising a casing, including a drying chamber and a communicating return passage for the continuous circulation of air from the passage through the drying chamber and back, air propelling means located in the passage, heat radiating means located at the ends of the casing, the latter having a charging opening with a closure means therefor, and an article supporting means adapted to be placed in the casing through the charging opening with the sides, top and bottom of said supporting means being spaced from the walls of the casing to permit the circulation of air around said article supporting means.

5. A drying machine comprising a casing, including a drying chamber and a communicating return passage for the continuous circulation of air from the passage through the drying chamber and back, said passage being enlarged to form a fan casing, a partition located in said fan casing having an opening, a fan located in said opening, heating elements located within the drying chamber in spaced relation, and an article supporting means disposed between the heating elements.

6. A drying machine comprising a casing, a horizontal partition mounted therein defining a lower drying chamber and an upper passagg, the ends of the partition being spaced from the ends of the casing to form a continuous path for the circulation of air, the top Wall of the casing being elevated at one point to form a fan casing, a transverse partition located in the fan casing and having an opening, a fan located in said opening, a pair of heat radiating elements located in the casing, one at each end of the drying chamber, said elements being of substantially equal radiating capacity, an intermediate heating element of lesser heating capacity, tray racks located between said heating elements, and trays carried by the racks in superposed spaced relation to support materials to be dried.

In testimony whereof, We have hereunto 15 signed our names at Philadelphia,- Pennsylvania, this 10th day of August, 1920. THOMAS ALLSOP. WALTER W. SIBSON. Witnesses JAMES H. BELL, E. L; FULLERTON. 

